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Lubov Fominskaja [6]
3 years ago
9

A family of four lives in a three-bedroom house and uses an average of 900 kWh of electricity per month. The family cools their

house for three months during the summer with two window-unit air conditioners that each use 350 kWh of electricity per month. Which of the following is the percentage of the family’s total annual electricity that is used to run the two air conditioners for the three summer months?
9,7%

19.4%

38.8%

77.8%
Chemistry
1 answer:
agasfer [191]3 years ago
5 0
<h2>Answer:</h2><h2>The percentage of the family’s total annual electricity that is used to run the two air conditioners for the three summer months = 19.4 %</h2>

Explanation:

Average electricity consumed per month = 900 kWh

The family cools their house for three months during the summer with two window-unit air conditioners

The power consumed by one window-unit air conditioners = 350 kWh

The power consumed by two window-unit air conditioners = 350(2) = 700 kWh

Power consumed for two air conditioners for the three summer months = 700 (3) = 2100 kWh

Total power consumed for 1 year = 900 (12) = 10800kWh

The percentage of the family’s total annual electricity that is used to run the two air conditioners for the three summer months = \frac{2100}{10800}100 = 19.4 %

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